Britain's Prince Harry is greeted by US Senator John McCain as he arrives at the Russell Senate Office Building in Washington D.C.Getty Images

WASHINGTON — Britain’s Prince Harry toured an exhibition about land mines, a cause dear to his late mother, Princess Diana, to open a weeklong U.S. visit devoted to the wounded victims of war.

For the prince, the tour in the halls of Congress was a world away from the Afghanistan war zone where he recently served for 20 weeks in an attack helicopter. It was just as far removed from his hijinks in a Las Vegas hotel room last year, when fuzzy photos got out of a naked Harry playing strip billiards.

One of America’s most storied wounded warriors, Republican Sen. John McCain, escorted Harry at the exhibition. On Friday, the prince visits Arlington National Cemetery and Walter Reed National Military Medical Center before flying to Colorado for the 2013 Warrior Games.